Heading into the Republican National Convention in Tampa, Fla., this week, Mitt Romney already faced a steep climb: The wealthy, guarded Republican presidential candidate needed to open up about himself and show voters that he understands the lives of average Americans and deserves their trust, political analysts say.

Now he must compete with tropical storm Isaac, which on Monday was bearing down on the Gulf Coast – an eerie echo of hurricane Katrina, from exactly seven years ago. At best, this unwelcome guest gives Mr. Romney a split-screen convention, as he competes for viewership with potentially dramatic footage of weather aftermath.

When Romney addresses the convention on Thursday, it will be his biggest moment in the national spotlight to date – and a crucial lead-in to his debates with President Obama in October. Polls show Romney in a tight race against an incumbent president with a weak economy and high unemployment. In other words, this race is winnable for Romney. But voters like Mr. Obama more than they do Romney, and history has shown that the more likable candidate usually wins.

To break out, Romney has to reveal more of himself to voters, said Republican strategist Karl Rove, appearing Monday at an event hosted by the news site Politico.

“They’ll hear a lot about tax cuts and large economic plans and Medicare reform packages, and blah blah blah blah blah, and that matters a lot to them,” says Mr. Rove, former George W. Bush political guru and a major force behind the American Crossroads "super political-action committee." “But they also want to know who is this person that is asking me to give them their vote to occupy the most consequential office in our country.”

Obama has done a good job of turning Romney into a caricature of the rich, uncaring businessman, Republicans say, and the time has come to turn that around – particularly with that sliver of the electorate that remains undecided and could determine the outcome.

“[Americans] have been told a bunch of terrible things about him – that he doesn’t care about people like you, that he ships jobs to China, that he’s a wealthy plutocrat married to a known equestrian,” former Republican National Committee chairman Haley Barbour told reporters Monday at an event in Tampa hosted by the GOP polling group Resurgent Republic.

In a way, then, Tuesday’s speech by Romney’s wife, Ann, is also significant, as she gives voters a perspective on the soon-to-be Republican nominee that no one else can. Expect to hear the story of a devoted husband who cared for and comforted his wife during serious health challenges.

“American people are going to see him and his family up close, and they are going to see that it’s a family that sets a high standard for all of us – that you’d like your kids to turn out like this,” says Mr. Barbour, the former governor of Mississippi.

Romney’s five grown sons – all launched in their own careers, all family men with a combined 18 children – have been present in the media this week and at events surrounding the convention, adding their personal testimonials to their father.

Dante Scala, a political scientist at the University of New Hampshire, Durham, agrees that Romney needs to build up voters’ comfort level with him as a person, but that may not be enough for them to entrust him with the presidency. Romney still needs to convince voters that he has a workable plan to turn the economy around, Mr. Scala says.

“A lot of those voters feel as if Obama hasn’t lived up to his promise – especially working-class whites who weren’t comfortable with him from the get-go,” he says. “But they’re not especially comfortable with Romney either.”

White working-class women, in particular, pose a challenge for Romney, and “he needs to find a way to distance himself from the Republican brand without turning off his base,” Scala says.

That brand took a major blow last week when Rep. Todd Akin, the Republican Senate nominee in Missouri, made a comment about women's bodies being able to prevent pregnancy in cases of “legitimate rape.” The messy spectacle of the Republican establishment, including Romney, trying unsuccessfully to get Congressman Akin to drop out made for a week of bad headlines – and opened up a fresh line of attack by Obama and the Democrats eager to exploit their wide lead among women voters.

The Akin fiasco also opened up a fresh fissure between two branches of the Republican Party – the hard-line social conservatives and those who emphasize economic conservatism. Whether Romney is able to help heal that rift is another open question during convention week.

He could well get assists from two other key speakers: his running mate, Rep. Paul Ryan of Wisconsin, and former presidential contender Rick Santorum. Both personally advocate for fewer exceptions on abortion than Romney, but at least in Congressman Ryan’s case, as running mate, he is going along with the Romney campaign position: allowances for abortion in the case of rape, incest, and a threat to the life of the mother.

Romney’s other challenge in holding the Republican Party together this week comes with the contingent who still fervently support libertarian Rep. Ron Paul (R) of Texas, Romney’s only challenger for the Republican nomination who never dropped out of the race. Congressman Paul held a separate event on Sunday that highlighted his displeasure with Romney as the Republican standard-bearer.

Analysts expect some Paul supporters to vote for Romney in November, but some could vote third party (say, by writing in Paul or voting for Libertarian Party nominee Gary Johnson) or just stay home.

But it’s the main stage of the convention that matters most to Romney, and whether he and his supporting cast of prime-time speakers can both excite the Republican base and attract undecided voters.

To Mr. O’Connell, the Republican strategist, Romney faces three tasks here in Tampa:

He has to tell people who he is and what he stands for.

He needs to demonstrate that the Republican Party is not just a party of old white men, but also one with vibrant constituencies of young people, Hispanics, and women.

“And third, he has to get a little specific about what he would do to get the economy on track,” O’Connell says. “But obviously he can’t say too much, or Obama raps him on the head.”